Accept-Ranges: (Response)

Introduction#

Accept-Ranges tells the client that this server will supports ranges for this resource (file).

Syntax#

• Accept-Ranges: RangeType
• Accept-Ranges: none

Parameters#

Remarks#

Accept-Ranges is part of the ranges system. The ranges system lets the client request only part of a file instead of having to download the whole file.

For example if a client only needs the last 100 bytes of a 10M file it can request the server only send data from offset 10485660 to 10485760.

Accept-Ranges is sent from the server to tell the client if it supports ranges. This only applies to this particular resource (file), other files may accept different range types.

Only two values are currently defined, bytes and none. The values bytes means that you can request byte ranges (offset and end will be in bytes). A value of ‘none’ means the server does not support ranges.

Clients are free to request byte range requests without checking if the server supports ranges.

The client uses Range to request a range from the server and the server replies with a status of 206 (Partial Content) if it is sending the range of bytes or 200 (ok) if it is going to send the whole file.

Server supports ranges

Request:”https://example.com”

GET / HTTP/1.1
Host: example.com
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:53.0) Gecko/20100101 Firefox/53.0
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: en-US,en;q=0.5
Accept-Encoding: gzip, deflate
Connection: keep-alive

Response:

HTTP/1.1 200 OK
Date: Sat, 01 Jan 2000 01:00:00 GMT
Server: Apache/2.4.10 (Win32) OpenSSL/1.0.1h PHP/5.4.31
Keep-Alive: timeout=5, max=97
Connection: Keep-Alive
Content-Type: text/html
Accept-Ranges: bytes
Content-Length: 500

Server doesn’t support ranges

Request:”https://example.com”

GET / HTTP/1.1
Host: example.com
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:53.0) Gecko/20100101 Firefox/53.0
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: en-US,en;q=0.5
Accept-Encoding: gzip, deflate
Connection: keep-alive

Response:

HTTP/1.1 200 OK
Date: Sat, 01 Jan 2000 01:00:00 GMT
Server: Apache/2.4.10 (Win32) OpenSSL/1.0.1h PHP/5.4.31
Keep-Alive: timeout=5, max=97
Connection: Keep-Alive
Content-Type: text/html
Accept-Ranges: none
Content-Length: 500